Patterns of immune, neuroendocrine, and cardiovascular stress responses in asymptomatic HIV seropositive and seronegative men

Immune, neuroendocrine, and cardiovascular system responses to an evaluative speech stressor and a mirror tracing stressor were studied in asymptomatic human immunodeficiency virus (HIV-1) seropositive and seronegative men. Because our previous work had shown abnormalities in adrenocortical response in HIV-1 seropositive individuals, we examined adrenocorticotropin (ACTH) and cortisol responses to the two behavioral challenges. Both ACTH and cortisol rose significantly to the speech stressor in the HIV+ and HIV groups. No increase in ACTH or cortisol to the mirror tracing task was observed in either group. Both the preparation of the speech and the mirror tracing task elicited comparable increases in blood pressure in each serostatus group, although the blood pressure elevations were supported by different mechanisms (i.e., cardiac output increases during speech preparation and total peripheral resistance increases during mirror tracing). The behavioral challenges induced distinctly different patterns of changes in absolute numbers of lymphocyte subpopulations and immune cellular function. The latency of the immune responses occurred prior to the increases in ACTH and cortisol, but concomitant with the blood pressure and cardiovascular changes. These findings suggest that trafficking patterns of the cellular immune response varied as a function of the stressor and were sympathetically mediated. In addition, differences between the HIV-1 seropositive and seronegative groups were observed in the total number of lymphocytes mobilized, and the CD4 and CD4/CD8 cellular responses to the behavioral challenges. Thus, although HIV-1 infection did not impact the acute cardiovascular responses, aspects of the immune response patterns were affected at an early stage of HIV spectrum disease. In contrast, the asymptomatic HIV-1 seropositive men at rest exhibited reduced myocardial contractility and stroke volume relative to the seronegative men.